Gas-alarm.



A. B. JAOBUS.

GAS ALARM.

APPLICATION FILED NOV. 2 4, 1909.

Patented Mar. 14, 1911.

THEtNaRms PETER: ca.wAsHmG1aN, n.4:

ALVAI-I IB. JACOBUS, OF KANSAS CITY, MISSOURI.

GAS-ALARM.

Specification of Letters Patent.

Patented Mar. 14, 1911.

Application filed November 24. 1909. Serial No. 529,820.

To all lwhom it may concern:

Be it known that I, ALvAH B. JAconns, a citizen of the United States, residing at Kansas City, in the county of Jackson and State of Missouri. have invented a new and useful GassAlarm, of which the following is a specification.

My invention relates to improvements in gas alarms in which an electric circuit is closed by means of air pressure acting upon the flexible wall of a chamber, containing the air, and suitable contact points when the chamber is surrounded by a gas lighter than the air contained within the chamber. I attain these objects by the mechanism illustrated in the accompanying drawings, in which- Figure 1 is a front view with the cover of the case removed and Fig. 2 is a vertical section taken on line A. B.

Similar numbers refer to similar parts throughout the several views.

A case made up of a back 1, sides 2 and 3, ends 4 and 5 and cover 6, contains an electric battery 7 and magneto bell 8. An air chamber 9 is formed by the partition 10 and. the lieXible diaphragm 11 which by the strips 12, 13, 14, 15. A flexible con ductor 16 is supported near the diaphragm 11 by the screws 17 and 18 and electric connection is made between the battery 7 and the conductor 16 by t-he wire 19 which is clamped to the conductor 16 by the screw 17 and to the battery 7 by the binding screw 20. A metallic bar 21 is supported between the sides 2 and 3 of the case by the screws 22 and 23. Near the center of the bar 21 is a threaded hole 24 into which an adjustable contact piece 25 is screwed. The screw 23 binds one end of the wire 26 to the bar 2l and the other end ot' the wire 26 is connected to the binding post 27 of the bell 8 by the screw 28. To the opposite binding post 29 of the bell 8 one end of a wire 30 is connected by the screw 31. The other end of the wire 30 is connected to the battery 7 by the binding screw 32. A hole 33 is cut through the upper part of the cover 6 and another hole 34 is cut in the end 5 of the case. These holes allow a free circulation of air is held in place or gas through that part of the 'case outside of the air chamber.

In the end 4 of the case is an opening 35 which allows air or gas to flow into the chamber 9. The opening 35 is protected from the force of air currents by the loop 36 which is fastened to the end 4 by the screws 37 and 38. The loop 36 also forms a `hanger for the apparatus.

4 The operation of the gas alarm is as foll'owsi he chamber 9 contains air of a weight corresponding to that of the surrounding atmosphere under normal conditions which causes an equal pressure on both sides of the diaphragm 11. When a gas or vapor lighter than air surrounds the case and circulates through it by way of the openings 33 and 34 the weight of the air in the chamber 9 causes an unbalanced pressure on the back of the diaphragm 11 forcing it out against the conductor 16 which in turn is forced against the contact piece 25 thus closing the electric circuit between the battery 7 and the bell 8.

Having thus described my apparatus, what I claim as my invention, and desire to secure by Letters Patent, ish

The combination, in a gas alarm, of an electric battery, a magneto bell, a case having a partition therein which forms a chamber at the back, and having a suitable opening at the top leading into the chamber and other suitable openings near the top and bottom leading into the space in front of the partition, an opening in the lower part of the partition covered by a flexible diaphragm, an adjustable contact piece supported in front of the diaphragm, an electric conductor suspended between the diaphragm and the adjustable contact piece and suitable electric connections making up a transmission circuit, all substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

ALVAH B. JACOBUS. Witnesses:

LAURA BECKLY,

GEORGIA B. JAooBUs.

Copies of lthis patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

